44 INHERITANCE IN RABBITS 



It is probable that in plants, as well as in animals, linear dimensions 

 are in general blending in their inheritance. In regard to the height of 

 maize, Lock (:o6, p. 130) says: 



Some of the strains which were made use of were uniformly much taller than others. In F t 

 the height of the cross-breds between such strains was obviously intermediate. In a number 

 of cases the cross was made between FI plants and the shorter of the parental types. The 

 offspring of this cross showed no such segregation into short and intermediate plants as was 

 to be expected if Mendel's law held good. On the contrary, the plants produced were re- 

 markably uniform in height. 



This account agrees precisely with our observations upon the inheri- 

 tance of linear dimensions in rabbits. 



The obviously blending inheritance of height in this case does not con- 

 tradict the known Mendelian behavior of the growth-habit in such plants 

 as the sweet pea, where Bateson (confirming Mendel) has shown dwarfness 

 to be alternative with tallness. Dwarfness is plainly such a discontinuous 

 variation in plants as is hypophylangia in man, and its inheritance is quite 

 different from that of ordinary variations in height. The former is a 

 discontinuous variation, Mendelian in its inheritance; the latter belongs 

 to a series of continuous variations, and is blending in its inheritance. 

 In a dwarf plant the internodes are shortened throughout the entire 

 plant, just as in a case of hypophylangia there is a general shortening 

 of the skeletal parts. 



